Patent GB-801433-A (GB)
Title: Improvements in windscreen cleaning systems
IPC: B60S1/48
Filed: 1954-09-23
Abstract: 801,433. Windscreen cleaners. TRICO PRODUCTS CORPORATION. Sept. 23, 1954 [Sept. 30, 1953], No. 27553/54. Class 138(1). A system for cleaning a vehicle windscreen, see Fig. 1, comprises a washer 11 for spraying liquid onto the windscreen, a wiper driven by a motor 4 and controlled by a valve 111, and a co-ordinator unit, Fig. 4, having a piston 26 slidably mounted with lost motion on a rod 27 connected to the valve 11<SP>1</SP> which is operated by engagement of the piston with the rod to start or increase the speed of the wiper motor when the washer 11 sprays the windscreen with liquid and, after the washer 11 ceases to spray the windscreen, stops or decreases the speed of the motor. The washer 11, Fig. 1, has a pneumatic motor 17 which expels a fixed quantity of liquid from a chamber 12 after filling the chamber from a liquid reservoir 11. The motor 17 is automatically actuated by energizing an electromagnetic valve 15 which connects the motor to the intake manifold of the vehicle engine. The valve is automatically tripped to open the motor 17 to atmosphere when the fixed quantity of liquid has been taken into chamber 12 and the energy of a spring-compressed during the intake stroke of the pump is utilized to expel liquid onto the windscreen. A cylinder 24 of the co-ordinator unit is connected by a conduit 31 to the washer motor 17 so that it is connected to the engine intake manifold together with and at the same time as the motor. The cylinder 24 can be shifted bodily axially on a bracket 21, Fig. 4, and contains the axially movable rod 27 on which is mounted the piston 26. A spring 28 biases the piston to one end of the cylinder which contains a check valve 33 bypassing a needle valve 36 for motion of the piston against the spring 28 but closing for opposite motion of the piston which is consequently slowed down while air escapes through valve 36. On evacuation of the cylinder 24 the piston compresses spring 28 and having taken up lost motion engages a shoulder 34 on the rod which is then constrained to force core 35<SP>11</SP> into the armour 35<SP>1</SP> of a Bowden cable 35. When the washer 11 trips its electromagnetic valve 15 when its charge of liquid is expelled, the cylinder 24 is opened to atmosphere and the piston 26 retires slowly under the action of spring 28 and on reaching an abutment 29 on the rod 27 returns the core 35<SP>11</SP> of Bowden cable 35 to its initial position. An arrangement whereby normal control of the wiper cannot conflict with control by the co-ordinator is shown in Fig. 2. The armour 35<SP>1</SP> of Bowden cable 35 is rigid with the cylinder 24 and with a slidably mounted L-member 37. The armour 9<SP>1</SP> of Bowden cable 9 is rigid with the wiper motor mounting and controls acceleration of the motor by pushing valve 11<SP>1</SP> by a head 39 on the core 9<SP>11</SP> which passes slidably through a limb of L-member 37. Core 35<SP>11</SP> of Bowden cable 35 is secured by a head 38 in an aperture 11<SP>11</SP> in the valve 11<SP>1</SP> and can either push or pull, i.e., accelerate or decelerate, the motor 4. With the piston 26 retired, as in Fig. 4, the head 38 holds the valve 11<SP>1</SP> and L-member 37 together so that normal control can be exercised by pushing or pulling on core 9<SP>11</SP> which will move L-member 37 and the whole co-ordinator bodily with the valve 11<SP>1</SP>. If the co-ordinator actuates the motor 4 the valve 11<SP>1</SP> is pushed to the left and the co-ordinator cylinder 24 is in a right hand position on the bracket 21. The head 39 of core 9<SP>11</SP> is therefore isolated and normal control suspended. If the wiper is already running when the co-ordinator functions the co-ordinator will be in a position to the left on bracket 21 and the valve 11<SP>1</SP> is first fully pushed home and then the co-ordinator forces itself to its right hand position. When the piston 26 retires the valve 11<SP>1</SP> is first withdrawn until it abuts the normal control head 39 whereafter the coordinator draws itself bodily back to its initial position on the bracket 21. Specifications 736,380 and 801,435 are referred to.